MSc

An experiment entitled "Production potential and economics of
sesamum-pulse intercropping in Onattukara tract" was conducted in the
summer rice fallows of Rice Research Station, Kayamkulam from
February 1998 to August 1998. The study also aims at estimating the
residual effect of the intercropping on succeeding crop of rice during
virippu season.
The experiment was laid out In randomised block design with
nine treatments in four replications. The weather condition during the
cropping period was congenial for crop growth. The treatments were
sole crops of sesamum, blackgram and greengram, intercropping of
sesamum with blackgram and greengram in 1: 1, 2: 1 and 3: 1 ratios.
The results indicated that sesamum in general, having a tall growing
habit was least affected by shade when put under intercropping systems
with pulses under different planting ratios. The association of sesamum
had lesser adverse effect on legumes and it was proved that legumes can
be grown in a compatible manner with sesamum.
The sole crops produced significantly higher seed yield than the
intercropping systems, in which yield varied due to differences in

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population. The sole crops recorded the maximum nutrient uptake values
due to more drymatter production as compared to intercropping
treatments.
The bio-economic suitability of the intercropping systems were
studied. Higher LER, LEe, Ree, Aggressivity and sesamum equivalent
were obtained in sesamum + blackgram in 1: 1 ratio and sesamum +
greengram in 2:1 ratios.
The results on monetary returns were higher in intercropping
systems irrespective of the pulse crops raised, compared to sole crop of
sesamum. The highest gross returns, net returns per rupee invested and
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benefit cost ratio were realised from the sole crop of blackgram. Among
intercropping systems, sesamum + blackgram in 1: 1 ratio gave higher
monetary returns and benefit cost ratio. The maximum monetary advantage
based on LER (Rs. 1219 hal ) was obtained when sesamum and blackgram
were grown in 1: 1 proportion.
The results on energy equivalents were also higher for sole crop
of blackgram and sesamum + blackgram in 1: 1 ratio.
In general, the soil nutrient status indicated a significant positive
buildup of nitrogen and phosphorus. But in case of potassium, the
exchangeable potassium was slightly reduced after the experiment. The
yield of succeeding rice crop was not significantly influenced by the
preceding crops combinations.

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Thus raising a sole crop of blackgram in the rice fallows of
Onattukara tract appears to be more profitable. Under the circumstances,
where an intercrop is desired for yield stability, to reduce risk or for
yield diversity, raising sesamum and blackgram in 1: 1 proportion can be
recommended as an economically viable and biologically sustainable
practice for the rice fallows of Onattukara region during the summer
season.